1. Field of the Invention
The present invention relates to an improvement in a time delay switch provided with an oil dash pot as a time delaying means.
2. Description of the Prior Art
Time delay switches works, for example to put a light off several minutes after a switch-off operation of a switch handle. Such switches are useful for lights of corridors or staircases or ventilators of a lavatory.
Recently, such delay time switch have been made to provide an oil dash pot as a time delay mechanism.
If such time delay switch is designed in a size of a single unit switch module alloted for ordinary simple home use wall switch for commercial power line, since the time delay mechanism using the oil dash pot delay means takes a certain space in the enclosure case of the switch, in order to afford as much room as possible for the switch the enclosure case must be made very thin, and such thin enclosure case has to be made of a thermoplastic resin which has higher durability against mechanical shock than a thermosetting resin. However, the thermo plastic resin has a problem that it has lower temperature resistivity and lower electric insulation than the thermosetting resin, and therefore, if the time delay switch is made by using the enclosure case of the thermoplastic resin, the durability is not sufficient.